Injury, infection and allergy of the eye stimulate inflammatory reactions. Humoral and cellular immunity are involved in many external eye diseases. Inflammatory corneal disease can be infectious or non-infections, and can be vision threatening. The infectious causes of ocular inflammation are numerous, and include bacteria, viruses, fungi and parasites. The initial events of exogenous ocular infections involve microbial adherence, invasion and multiplication. Recurrent viral infections can also cause ocular inflammation.
The initial stages of ocular inflammation, such as inflammation of a surface of the eye, are often non-specific. These early manifestations include pain, warmth, redness and swelling. Common symptoms of inflammatory disease of the outer eye are itching, discomfort, dryness, redness, tearing, discharge, and blurred vision.
The most common cause of redness in the eye is conjunctival inflammation. Common causes of conjunctivitis include papillary conjunctivitis, follicular conjunctivitis, conjunctival granuloma and conjunctival ulceration. Keratitis is inflammation of the cornea. Common causes of keratitis are corneal injury, dry eye syndrome, viral infections such as adenovirus, herpes simplex, and varicella-zoster infections, bacterial infections, fungal infections, and autoimmune disorders. There is a need for methods for treating ocular inflammation, including keratitis and conjunctivitis.